The Pathology Core is responsible for all the morphological assessments of various strains of mice injected with Theiler's virus, or immunized with myelin antigens for development of experimental autoimmune encephalomyelitis. The Pathology Core is housed in Dr. Rodriguez's research laboratory. The major focus of the Pathology Core is primarily on plastic-embedded sections embedded in either glycol methacrylate or Araldite. These are the standard assays for assessment of demyelination, remyelination, spinal cord atrophy, and axonal loss. In addition, brain and spinal cord sections are embedded in paraffin for immunocytochemistry and in situ hybridization to detect virus replication. Frozen sections are used for immunofluorescence staining for neurofilament proteins. T cell and cytokine expression and [3H] saxitoxin-labeling to assess axonal integrity.